Svayambhu (...) is a Sanskrit word that means "self-manifested", "self-existing", or "that is created by its own accord". In Tibetan, this word appears as "Rangjung" རང་བྱུང་ .

Often, the word swayambhu is used to describe a self manifested image of a deity, otr ku (Tibetan) which was not made by human hands, but instead is naturally arisen, or generated by nature. Rangjung in Tibetan language or in Dzongkha expresses the concept of a self-arisen manifestation. Throughout the Tibetan cultural sphere there are sacred seed syllables, mantras or depiction of deities that a presumed not to be man-made, but "rangjung", self arisen or autogenic. For example, in the Jokhang Temple in Lhasa is a rangjung goat's head in a side chapel protruding out of a big rock.

The word etymology of swayambhu is 'Svayam' (...) which means 'self' or 'on its own' and 'bhu' (..) which means 'to take birth' or 'arising'. This is applicable to the physical and tangible idols of Gods that we see or to the intangible yet existing God whom we cannot see. For example, the jyotirlingas are considered swayambhu- the idol of Venkateshwara at Tirumala and some other ones are considered Swayambu- which means they are not installed by any person but they exist on their own. The word Swayambhu is also applicable to Gods- for example- Brahma is described as swayambhu in Ramayana, Vishnu is called swayambhu in Matsya purana.
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